Circulation | 2019
Cardiovascular Outcomes in the Wake of Financial Uncertainty: A Double Hit
Abstract
The taxonomy of financial toxicity is growing as we learn more about the devastating toll of various financial hardships on people’s health and health outcomes1; specifically, cardiovascular outcomes.2 Poverty has long been known to affect rates of hypertension, diabetes mellitus, obesity, heart attacks, and strokes.3,4 Financial burden, which describes the relative inability to afford basic goods (captured as not having enough to make ends meet, or the burden of out-of-pocket costs of medications and needed medical care), is also associated with worse outcomes after myocardial infarction.5,6 More recently, wealth shock, a term applied to individuals who experience significant losses during times of economic recession or depression, such as with the loss of stocks, has been associated with premature mortality.7 In this issue of Circulation, Elfassy et al8 add to this taxonomy of financial toxicity the construct of income volatility, defined as fluctuations in income that typically involve steep losses. They present data from the CARDIA (Coronary Artery Risk Development in Young Adults) prospective cohort study, assessing determinants of future cardiovascular disease among individuals aged 30 to 45 years. Their primary aim was to describe the relationship between changes in income during a 15-year period and the probability of having a cardiovascular event or dying from any cause in the subsequent 10-year period. Income volatility was categorized into tertiles of low, medium, and high income volatility based on the intraindividual standard deviation of the percent change in inflation-adjusted income, self-reported at 5 time points between 1990 and 2005. Because both increases and decreases in income are detected by this metric, the authors also examine the effect on cardiovascular outcomes of income drops alone, including the number of income drops and large income drops (defined as >$20 000). Perhaps not surprisingly, they find that income volatility experienced early in life is associated with premature cardiovascular disease and all-cause mortality. In addition, they find a positive correlation between both the number of income drops and the extent of income loss with the likelihood of having an adverse cardiovascular event. Moreover, the observed effects were striking: high income volatility and ≥2 income drops over 15 years were both associated with a 2-fold risk of cardiovascular disease and mortality, whereas large income drops were associated with a 3-fold increased risk. Income volatility, as with many other forms of financial hardship, may act through a variety of mechanisms to affect health outcomes. In general, chronic financial stress can be associated with increased allostatic load, in which increased levels of inflammation and neurohormones alter physiological responses, including blood pressure, endothelial function, and sympathetic output. Plausibly, income volatility may result in more acute or dramatic physiological shifts. For example, job © 2019 American Heart Association, Inc. Circulation